Iran’s semiofficial Fars news agency said a bomb blast killed a university professor, in an attack coinciding with the second anniversary of an explosion that killed a senior Iranian nuclear scientist.

Fars said an assailant on a motorcycle attached a magnetic bomb to the car of Mostafa Ahmadi on Wednesday morning, killing the professor and injuring two others. The incident took place near Gol Nabi Street in north Tehran, it said.

It was not immediately clear if Ahmadi was involved in Iran’s nuclear program, or in what department he was teaching.

However, several Iranian nuclear scientists have been assassinated in recent years.

Tehran has blamed the killings on Israel and the US. Both countries deny the accusations.